It is well known that contact lenses can be used for cosmetics and the correction of visual acuity. The ideal contact lens is one which is not only comfortable to wear for extended periods of time, but also easily manufactured at minimum cost in time and labor.
Generally, the front, or convex, surface of a contact lens comprises an optic zone, one or more peripheral zones that are adjacent to the optical zone, and an edge, wherein the peripheral zones are typical sphere surfaces. The presence of all but the optic zone is necessitated by the need for the contact lens to fit comfortably, for the lens to position itself correctly on the wearer's eye, and for the lens to be easily handled by the lens wearer.
However, where the optical zone is an aspherical surface, the use of one or more peripheral zones that are adjacent to the optical zone is problematic. For example, the peripheral zone forms a junction with the optical zone, which may comprises flexion points at the junction. Such flexion points may result in differential pressure on the wearer's eye and therefore may have adverse effects on the comfort and ocular health. Therefore, there is a need for a contact lens that overcomes some or all of these disadvantages and can be easily manufactured at minimum cost in time and labor.